Coordination and Control

Explain how impulses in the sensory neurone can stimulate the relay neurone.

Analgesics are drugs that help to stop a person from feeling pain.

Fig. 8.2 shows the shape of some analgesic drug molecules.

Suggest how this analgesic drug can help to stop a person from feeling pain.

Use information from Fig. 8.1 and Fig. 8.2 in your answer.

Explain the differences between organs, tissues and cells, using the eye as an example.

Synapses are found in the mammalian nervous system.

Explain how the structure of a synapse ensures that electrical impulses travel in one direction only.

You may use the outline of a synapse in Fig. 7.1 to illustrate your answer.

Describe the ways in which the human and the plant coordinate their responses to these beams of light.

Your answer should include:

• stimulus detection
• method of responding.

human ______

plant ______

Describe the role of synapses in a reflex arc.

Name the two parts of the central nervous system labelled A and B.

A ______
B ______

This reflex action involves a receptor and an effector.

On Fig. 3.1, draw a label line to the location of:

• the receptor and label it R
• the effector and label it E.

Describe the roles of two named neurones in this reflex arc.

Name gland C.

______

Explain the role of gland C in triggering an increase in heart rate in response to a sudden shock.

During the period of time shown in Fig. 4.1, the person carried out each of the following actions:

P read the words in a book
Q read the time on a wall clock
R looked out of a window at a bird high in the sky.

Identify in what order the person carried out actions P, Q and R.

Place the letters P, Q and R in the correct order below.

______ $\rightarrow$ ______ $\rightarrow$ ______

At the time labelled H on Fig. 4.1, the shape of the lens is changing. Outline, with reference to named structures in the eye, how this change happens.

Complete the labels on Fig. 4.2 by naming the two parts of the eye indicated by the label lines.

Complete Fig. 4.3 to show a view of the same eye as it would appear in bright light.

State the type of nervous response that takes place when the eye changes its appearance from that in Fig. 4.2 to that in Fig. 4.3.

______

Suggest the importance to the person of this response taking place in the eye.

Describe what is meant by the term hormone.

______

The list shows some of the hormones produced by the human body:

A adrenaline
B luteinising hormone
C insulin
D progesterone
E oestrogen
F glucagon.

Complete Table 1.1 by writing the correct letters in each box. Each box can contain one or more letters and each letter can be used more than once. The first one has been done for you.

Table 1.1

Identify the parts labelled B and C.

B = ______
C = ______

Describe how part B is involved in maintaining a constant body temperature when the external temperature drops.

Part A is unevenly distributed in human skin.

Name part A and suggest reasons for this uneven distribution.

The thickness of layer D can change over several months.

Suggest and explain one reason for a decrease in the thickness.

Compare these two types of coordination.

A girl sees a vehicle travelling towards her at speed as she crosses a road. This triggers nerve impulses and the release of adrenaline in her body.

Describe the role of the nerve impulses and adrenaline in helping her to react to this situation.

Label on the diagram the parts of the brain identified in the table, using label lines and the letters A to D only.

Name one structure in the skin that receives impulses from part B of the brain to control body temperature.

______

Outline how the action of this structure results in the control of body temperature.

Complete the table showing different parts of the nervous system, their location in the human body and some of their functions.

One row has already been completed.

A man is threading a needle.

To do this, each of the man's eyes produces a focused image of the needle.

Explain how different parts of the eye function to produce a focused image of a near object.